More evidence that chronic cardio is not healthy: increased arterial plaque in committed marathon runners.
It's an interesting investigation, but an observational study with a sample size of fifty people simply does not merit the claim. With a sample size this small, randomness is likely to overpower any true statistical trends. Not to mention, there are many other factors that could be influencing these runners' increased plaque -- perhaps a high carbohydrate grain based diet to fuel their running efforts. I do like that one scientist proposed that this trend could be explained by the runners being in a constant state of high inflammation.
It's nice to see this sort of stuff break into mainstream media though... at least CW is being questioned.